Tn552-derived regions on pWBG753 and pWBG731. (A) Gene maps of the Tn552 and Tn552-like sequences on pI9789, pWBG753, and pWBG731, showing the positions of the right and left terminal inverted repeats (TIRR and TIRL, respectively), resL sites, and other genes or insertion sequences. (B) Sequence alignment of the resL sites on the same three plasmids. The region of the resL site is the main recombination site of the resL region “subsite I.” Accessory subsites II and III are identifiable upstream of the binL and res3 coding sequences.